Roland G-505/GR-300 upgrade

Back in high school, thanks to my older brother, I got hooked on Bill Frisell’s early recordings for the ECM label. Not only was Frisell’s playing hypnotic and beautiful, but the sound of his rig, particularly on albums like “Rambler”, was an other-worldly mystery I found totally captivating. It took a while for me to figure out how he was getting that sound: the phenomenal (and WAY ahead of its time) Roland GR-300 guitar synthesizer. Developed in the late 1970s, the GR-300 remains the holy grail of guitar synthesis – all analog, incredibly responsive, and boasting a filter just as fat and gorgeous as the best analog keyboard synthesizers of that period. Being a bit of an analog synth nut as well, it was inevitable that, at some point, I was going to head down the guitar synth rabbit hole.

Roland offered a few different guitars that could interface with the GR-300 and their other synths like the GR-100 and GR-700. The G-303 has long been considered the best sounding of them all, popularized by the incredible Pat Metheny. But it could also be found in the hands of Robert Fripp, Adrian Belew, and a number of other innovative guitarists who were pushing the sonic envelope in the 1970s and 1980s. Roland also produced the G-808, a neck-through version of the 303, and the G-505, which was a Strat-style guitar with single-coil pickups, a tremolo, and a pickguard. It was a closed system – in order to drive the GR-300, you had to have the hex pickup and control circuitry available only on a Roland guitar. Although Roland released an add-on hex pickup for retrofitting non-Roland guitars, the system continued to rely on their proprietary 24-pin cables to connect the guitar and synth together. Eventually these cables were as, if not more, sought after than the instruments themselves. After Roland shifted to its present 13-pin system for new guitar synths, the only source was the used market, and prices shot up accordingly (up to $400 for a 30-year-old cable!). Enter Wayne Joness.

In my hunt for more information about Roland guitar synths, I came across Wayne Joness’ awesome www.gr300.com site. Wayne spent years accumulating information about Roland guitar synths (as well as a few from other manufacturers), and developed a number of modifications, including updates on early mods designed by Craig Anderton (of Electronic Projects for Musicians fame, among other things). Wayne’s site has been an invaluable resource for anyone interested in Roland guitar synths, including PDF copies of original user and service manuals, detailed descriptions and parts lists for various mods, and tons of pictures. Among his greatest contributions is the 24-to-25 pin conversion mod, which eliminates the dependence on old, expensive 24-pin cables by swapping them for readily available 25-pin connectors and cables. The ribbons Roland used to link the cable connectors to the synth boards also means that, if you happen to have some spare ribbons around, the conversion is reversible – no permanent changes are necessary to either the guitar or the synth for this to work.

Knowing it was possible, with a bit of soldering, to banish the cable issue made getting in to a GR-300 system much more viable. So I picked up a GR-300, a sunburst G-505, and set about making the modifications to the cabling system. The original connector included a metal mounting plate that screwed into the cavity cover assembly, so I designed a plastic mount for the new connector that could be mounted to the cover with the original screws. I also made several mods to the guitar, including making a new pickguard, installing a new Wilkinson VS100 tremolo system, refretting the neck, adding locking tuners and a new graphite nut, and new pickups and selector switch. The photos below detail some of my process. Many thanks to Wayne for making the info on how to do this available.